The present disclosure relates in general to energy generation systems and/or energy consuming systems, and in particular to determining the location of a load meter for monitoring such systems.
In recent years, climate change concerns, federal/state initiatives, and other factors have driven a rapid rise in the installation of renewable energy generation (EG) systems (i.e., systems that generate energy using renewable resources such as solar, wind, hydropower, etc.) at residential and non-residential sites. Solar photovoltaic (PV) systems, in particular, have been very popular EG systems.
Typically, this PV capacity is coupled to the main panel (i.e., main line) and available to power all circuits at the site. Additionally, the PV circuit can be “grid connected” such that any over generation (e.g., PV generation that is greater than the immediate load requirement) can be fed back to the utility through the on-site main panel. This may result in a credit on the site owner's electricity bill and allow the benefits of this energy to be conveyed to others on the grid.
In order to determine how much energy should be provided or credited to a site load, a monitoring device, such as a load meter, is typically installed at a site. For instance, the load meter is installed in an electrical box at a residential site. The load meter continually monitors the energy consumption of the site and/or the PV energy production for a specific period of time. Data generated from the load meter is communicated to a server computer, which uses the data to calculate the amount of energy to be provided or credited to the site load. Proper calculation of such amounts of energy is highly dependent upon whether the server computer knows if the data provided by the load meter takes into consideration the PV energy produced by the PV system.
Whether the data provided by the load meter includes the PV energy produced by the PV system is generally dependent upon the location of its installation relative to the location of the PV system. For instance, the load meter can be installed either upstream or downstream from the PV system. Positioning the load meter upstream from the PV system enables the load meter to measure the net load of the site, i.e., the gross load of the site compensated by the PV energy produced. Alternatively, positioning the load meter downstream from the PV system enables the load meter to measure the gross load of the site, i.e., the site load without any compensation from the PV energy produced. If the server computer does not know that the load meter is measuring only gross load, the server computer may inaccurately calculate energy consumed or produced by the site because it does not account for the PV energy production. An inaccurate calculation can result in an overcharge for excess energy provided, wasted energy, and, ultimately, an increase in cost.
In addition to the problem aforementioned herein, present installation methods do not ensure that the load meter is installed upstream from the PV system. This could be for several reasons. One reason may be that the installation method calls for an indiscriminate placement of the load meter and does not require its location to be recorded. Another reason may be that the electrical box is configured in a way that prevents the load meter from being installed upstream from the PV system, and the electrician forgets the location of the load meter or cannot be located to inform the location of the load meter. In either situation, the location of the load meter is not known and may lead to inaccurate readings.